TPO and synovial sarcoma: For example, desmin was positively expressed in rhabdomyosarcoma.[28] And muscle-specific actin (MSA) is positively expressed in leiomyosarcoma.[29] Vimentin and cytokeratin antibodies were used in combination to identify carcinosarcoma and synovial sarcoma, respectively.[30] Positive expression of myogenin and/or MyoD1 is helpful in the diagnosis of spindle cells or sclerosing rhabdomyosarcoma.[31] Carcinosarcoma was considered if the tumor expressed both the carcinomatous and sarcomatous components.